Śatapatha Brāhmaṇa ("of a hundred paths") 6.6.3.5

6.6.3.5

athāparaśuvṛkṇamādadhāti | jāyata eṣa etadyaccīyate sa eṣa sarvāsmā annāya jāyata etadvekamannaṃ yadaparaśuvṛkaṇaṃ tenainametatprīṇāti yadagne kāni kāni cidā te dārūṇi dadhmasi sarvaṃ tadastu te ghṛtaṃ tajjuṣasva yaviṣṭhyeti yathaiva yajustathā bandhustadyatkiṃ cāparaśuvṛkṇaṃ tadasmā etatsvadayati tadasmā annaṃ kṛtvāpidadhāti

He then puts on one not cut by an axe,--that (Agni) is born when he is built up: it is for all (kinds of) food that he is born. Now that (wood) not cut by an axe is one kind of food (for the fire): it is thereby that he now gratifies him. [Vâg. S. XI, 73; Rik S. VIII, 102, 20] 'Whatsoever wood we lay upon thee, O Agni, let all that be ghee unto thee, do thou relish that, O youngest!' as the text, so its meaning: whatever (wood there is) not cut by the axe, that he makes palatable to him; and having made it food for him, he sets it before him.